Using the green anole lizard, Anolis carolinensis, as a model, I propose to investigate further the possible evolutionary origins of physiological and psychological influences upon reproductive behavior as well as how behavioral controlling mechanisms function to adapt organisms to the environment. To this end, studies of the physiological control of species-typical behavior and of the stimulus control of hormone secretion are planned. Research on the psychobiology of reproduction of snakes is also proposed. Specifically, the hormonal regulation of male reproductive behavior will be investigated and the hormonally-dependent male and female sex pheromones critical to the coordination of reproductive behavior isolated and characterized. Studies designed to test in the field hypotheses arising from laboratory research on pheromone communication in snakes are also proposed.